Accomplishments: We examined ovarian cancer risk in relation to use of phenolphthalein-containing laxatives in 410 epithelial ovarian cancer cases and 713 controls. Compared to women who never used a laxative, ever use of a phenolphthalein-containing laxative was not associated (OR 1.1, 95% CI 0.9 !1.4) with an increased risk of ovarian cancer. Risk was slightly higher with more frequent use (OR 1.2 for 75 or more days of use). When women who used non-phenolphthalein containing laxatives was used as the reference group, the associations were slightly larger: OR 1.4 for any use of phenolphthalein-containing laxatives and OR 1.5 for 75 or more days of use.